Ink supply for picture recorders



July 12 1927;l

NK SUPPLY FoR'PIcTbRE REcoRDERs I Filed Aug. 19, 1925 VIL E 7 INVENTOR RIC ARD H. RANGER Patented July 12, 19,27.

UNITED ASTATES PATENT OFFICE.

RICHARD ROWLAND RANGER, or NEWARK, NEW JERSEY, AssIGNoR To' RADIO coR PORATION OF AMERICA, I .A CORPORATION OF DELAWARE.

INK SUPPLY FOR PICTURE RECORDERS.

Application led August 19, 1925. Serial No. 51,192.

This invention relates to certain new and useful improvements in the art of facsimile telegraphy and more especially to an'ink or .marking fluid supply system for a. pen,such as is used in the receiver of` a facsimile telegraph system.

Experience has Shown that in the ordinary types of receivers in which a pen is used that is not constantly in contact with paper,'there is a tendency for the marking fluid or ink to dry up on the point of the pen and impede thev flow of marking fluid. If this drying up is sufficient to completely stop the flow of marking fluid, a portion of the picture may vbe lost, but even if it is not. suflicient to com pletely stop the flow of marking fluid, it may nevertheless still be suflicient to considerably impede the flow and result in portions of the record being light which would be dark.

In practice, when this condition is found the operator will generally apply more pressure to the marking fluid by raising the supply reservoir. This generally results in a pressure being supplied which is sufficient to force the marking fluid out in greater volume than before, producing in the final record .a marked .contrast of light and dark bands in the record.

' I have found that this difficulty can be l avoided by supplying ink to the pen, not at constant pressure as has heretofore been the case, but by sup lying to the pen a constant quantity. of mar ing fluid at a variable pressure. In other words, a power driven pump is used for forcing marking fluid from a supply reservoirto the pen and this pump is so adjusted as to feed through the quantity of marking fluid which experience has shown is necessary. x

If the marking fluid at the point of the pen dries or comes in a way toimpede the flow of marking fluid, the pressure will rise due to the action of the pump until it reaches a valuesuflicient to push the obstruction aside. Immediately-j when this occurs, the

pressure will fall again andthe `normal flow.

of ink willv be resumed.

It is an object of this invention to reduce sure suflicient to cause marking fluid to be deliveredfat all times.

It is a further object of this invention to produce an .ink supply system which is selfcleaning and in which the variations in tone. of the record, .due to inequalities in the ink supply, are decreased.

The lnovel features which I believe to be `characteristic of my invention are set forth with particularity in the l.appended claims. My invention itself however, both as to its organization and method of operation to' gether with further objects'and advantages thereof, will best be understood by reference to the following description taken in connection with the accompanying drawing, in i other end to a suitable pen or stylus 3. Thev tube 2 is coiled .aroundl within a yhollow cylindricalshell 4, preferably butfnot necessarily of "metal A shaft 8 is provided adapted 4to be driven kby any `suitable source, such for instanceas a motor having suitable step-down gearing. The shaft x8 .is provided with anv` extension at right angles ,thereto designated as7 and 'upon theend of the' extension 7 there is mounted a roller 6.

Furthermore, I find it preferable to provide a cylindrical shell preferably of metal for the purpose of applying the pressure developed by roller 6 uniformly :to the tubing 2, although it will be understood that ifk desired the roller 6 may be made sufciently long to extend over aynumber of turns of the' tubing 2 .and shell 5 Imay -be omitted.

'- In operation the reservoir which willbe filled with marking fluid and vthe motor whichdrive'sthe shaft-,8 will be set into operation. After the tube 2 has become filled with markingfluid, the fluid will be delivered from the pen 3 ata rate determined by the speed of the operation ofshaft- 8, whichl may be regulated to feed theamount desired.

10orv proach tothe pen 3, whereby Ithe marking iiuid will be forced through the tube.

. While I have shown and ldescribed one embodiment of my invention, it will be clear that I am not limited thereto, but that other arrangements may be employed if desired without departing from the scope of my invention. i

Having described my Ainvention,what I .claim is:

l. In a graphic recorder utilizing marking luid, the combination of a marking stylus, a marking fluid reservoir and powerl driven means for supplying fluid from said reservoir to said stylus under the positive pressure.

2. In a graphic recorder utilizing marking fluid, the combination of a marking Stylus, smarking fluid reservoir and means for supplying a constant quantity of Huid at a varying pressure per unit of time comprising a positive pressure pump.

3. In a graphic recorder, means for Supt plying a constant quantit of'fluid per unit` ottime comprising a eXi le tubing for conveying marking fluid, a hollow cylindrical shell having at leastone turn of Said tubing disposed interiorly thereof in the form of a. helix and a rotating arm for compressing said tubing. y

4. In a graphic recorder a reservoir of marking fluid, a marking stylus, an elastic tube therebetween, cooperating therewith, and having a portion thereof coiled, and a positive pressure means cooperating with said coiled portion for pinching portions 'of said coiled tube into successive separate moving chambers.

RICHARD H. RANGER. 

